1	The Life Cycle of a Lithic Knife Form A Morphometric Study of Archaic Bevel Resharpening Copyright 2004 Long, D. and Fisher, J.
2	About the Study Team Dan Long; Chippawa, Ontario– Master Flintknapper & Lithic Technologist; responsible for the creation and reduction of the point seen in this presentation. Jim Fisher; Grand Island, NY – Avocational Archaeologist / Lithic Analyst; reduction sequence imaging, managed morphometric data collection & analysis,.
3	What is Morphology? Morphology: the study of form and structure Morphometric studies define changes in form and structure utilizing precise measurement
4	Purpose of the Study To illustrate the effect of multiple series of resharpening on Archaic Bevel lithic knife forms (Dovetail & Thebes Clusters) To further the identification & understanding of morphometric "markers" as they may be applied to postulations regarding authentic knife forms of the Archaic Bevel clusters
5	Objectives of the Study Quantify the number of successive resharpening series necessary to bring the subject knife form to terminal utility ( def. point at which the form no longer supports practical use as a knife) Identify morphometric markers that may indicate limits of alternate-face bevel knife resharpening
6	Method A reproduction Dovetail knife of Burlington Chert was created for the study The blade margins of the knife were subject to abrasive grinding to simulate use wear The blade margins were retouched, or resharpened, via pressure flaking and morphometric data was recorded at each successive interval
7	Morphometric Model The data set resultant of this project was collected using many of the morphological attributes metrically defined by Tara L. Prindle in her projectile point identification program, entitled POINT (version 1.0, 1993). One additional variable, Blade Torsion, is specific to the morphology of lithic knives belonging to the Early Archaic alternate-face beveled cluster. The Blade Torsion morphometric rank order for this study was devised by J. Fisher.
8	Data Collected Point Width (PW) PW = maximum width of point perpendicular to the length in mm; measured at median point of unused blade margin.
9	Data Collected Point Length (PL) PL = maximum length of point (tip to base) in mm
10	Data Collected Blade Curvature (BC) BC = Rank of lateral blade margin height measured from a line drawn from the tip of the point to the corner of the shoulder.
11	Blade Curvature Rank Very Convex >=5 mm Convex <5 mm & >=2 mm Straight <2 mm & >-2 mm Concave <=-2 mm Mixed <2 mm & >2 mm
12	Data Collected Shoulder Angle (SA) SA = angle of the shoulder measured by drawing a line from the top of the notch to the shoulder, and from the corner of the shoulder to the tip.
13	Data Collected Blade Torsion (BT) BT = rank of blade margin position relative to the parallel axis of blade margins and base, or centerline, in unused condition (BU).
14	Blade Torsion Rank Slight >0 & <=1 mm Mild >1 mm & <=3 mm Moderate >3 mm & <=4 mm Severe >4 mm
15	Calculated Point Attributes Point Ratio (PR) PR = Point Width (PW) divided by Point Length (PL) PR=PW/PL PR relates the width of the blade at the lateral margins as a percentage of the total length of the blade; indicates the degree to which the point is becoming more narrow relative to length.
16	Calculated Point Attributes Point Width Reduction (PWR) PWR = Unused Point Width (UPW), expressed as 100%, minus Resharpened Point Width (RPW) divided by UPW PWR = 100 – (RPW/UPW) PWR relates the percentage of Point Width lost as a result of each series of resharpening
17	Calculated Point Attributes Point Length Reduction (PLR) PLR = Unused Point Length (UPL), expressed as 100%, minus Resharpened Point Length (RPL) divided by UPL PLR = 100 – (RPL/UPL) PLR relates the percentage of Point Length lost as a result of each series of resharpening
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43	Observations Terminal knife form utility occurred at 5.75 mm BT & 65 degrees Blade Torsion Angle (BTA) Terminal knife form utility occurred at 65% PWR At RS#17 increase in step fractures made resharpening impractical The curvature of the blade creates a variance of BTA at the pressure flaking platform of approximately 15 degrees, actual BTA approaches 80 degrees The measure of BTA and variance in BTA were only measured at the point of terminal utility of the knife form – these were significant morphometric markers
44	Significance of Blade Torsion Blade Torsion Angle (BTA) BTA = angle created by the plane of the bevel relative to centerline of blade in unused condition (BU)
45	Significance of Blade Torsion Blade Torsion Angle variance (BTA)
46	Study Questions for Future Consideration Will additional trial data, or morphometric data from authentic Archaic Bevel knife/drill forms, correlate (within a nominal range of deviation) to the measures of BT, BTA, and PWR as suggested in this initial trial? What data set will be resultant of trials using other Archaic Bevel point types or types that exhibit bifacial resharpening?
47	Questions?
48	More Information About the Authors http://knapper_dan.tripod.com Dan Long’s Flintknapping website pacheydan@sympatico.ca www.creeksideartifacts.com Jim Fisher’s Avocational Archaeology & Lithic Technology website jim@creeksideartifacts.com